The ability to locate and track assets, such as devices, products, persons, equipment, vehicles, etc. is important in many applications and industries. For example, in construction areas someone may wish to track equipment (e.g. equipment, tools), manufacturers may wish to track parts in an assembly plant and warehouses may wish to track supplies. In some applications, assets may be monitored using wireless tags that communicate using wireless signals from a transceiver device. In such applications, a wireless tag may be attached to an asset and may be configured to transmit information to a transceiver. The information may comprise device identification, telemetry and even location information associated with the tag. In other applications, mobile phones are located and tracked instead or in addition to tags.
In some cases, the transceivers that are in communication with the mobile devices (e.g. tags, smartphones, wearable devices, laptops, tablets, etc.) may be fix-installed in a known place. The known place of the transceivers may be used by the location or tracking system to estimate the position of the mobile device (e.g. tag, phone, wearable device, laptop, etc.). Received Signal Strength (RSS), Time-of-Arrival (TOA), Angle-of-Arrival (AoA), two-way ranging and other techniques are commonly used to estimate the position of the mobile device.
Problems can arise, however, when the deployment of transceivers in fixed places (e.g. poles or buildings) in a certain area is not cost effective, not feasible or even not permitted. For example, this may be the situation when locating assets in a construction site where it may be expensive to fix install those transceivers, even when they are battery operated. In another example, the radio regulations of a specific country may not allow the transmission of certain wireless signals (e.g. UWB) from static devices operating outdoors.
Accordingly, methods and systems consistent with the disclosed embodiments provide an improved method to locate mobile devices in certain type of areas.